Question about LPG heaters in cold areas

So up in Hokkaido, there's these tiny kerosene heaters that basically vent directly into the room. For some reason, everyone loves to use these even though they shut off every 3 hours (for safety purposes) and leaves you freezing at 2am in the morning.

I was looking into LPG heaters (that hook into the LPG line which powers the cook top) and i noticed that while some of them have FF exits, a lot of them do not, and also vent directly into the room.

I have never had experience with this – does anyone know if these also have a 3h shut off timer (that cannot be disabled)? ChatGPT is telling me its 3 / 5 / 8 but i cant find any actual sources on this.

by saibalter